Treatment of textile and other materials



Jan. 3, 1939. H. DREYFUS ET AL TREATMENT OF TEXTILE AND OTHER MATERIALS 2 Sheets-Sheet 1 HENRY DREYFUS ROBERT W. MDNCRIEFF WILUHM M GLASS INVENTORS Jan. 3, 1939. H. DREYFUS ET AL TREATMENT OF TEXTILE AND OTHER MATERIALS 2 Sheets-Sheet 2 Filed March 18, 1937 ROBERT ATTORDIE Y5 Patented Jan. 3, 1939 OF TEXTILE AND OTHER MATERIALS Henry Dreyfus, London, and Robert Wighton' Moncriefl' and William Macintosh Glass, Spondon, near Derby, England, assignors to Celanese Corporation of America, a corporation of Delaware Application March 18, 1937, Serial No. 131,664 In Great Britain April 14, 1936 14 Claims.

derivative of cellulose, wherein they are stretched in the presence of steam by means of an apparatus which comprises a steam chamber and an end pressure chamber which contains compressed air or other compressed inert gas. The use of an end pressure chamber in combination with a steam stretching chamber renders it possible to obtain a greater tenacity than is possible without such end pressure chamber. It also describes processes for the stretching of foils, films and similar materials in the presence of steam, and for stretching and other treatments of filaments, foils and similar materials in the presence of hot water and other agents under pressure. scribed in the above specification apparatus may be employed which comprises only a single end pressure chamber, or an end pressure chamber may be provided at each end of the pressure treatment chamber.

In carrying out stretching processes such as are described in the specification referred to above using steam or hot water it has been found that a gradual heating up of the medium in the end pressure chamber or chambers may occur, particularly if the pressure therein is below that in the stretching chamber so that steam or hot water flows into the end chamber or chambers. It

has now been discovered that a further improvement in the tenacity of the materials may be obtained by reducing or preventing this heating up of the medium in the end pressure chamber or chambers. v The invention also renders it possible to obtain yarn of decreased compactness.

According to the present invention, therefore, artificial filaments and similar materials having a basis of cellulose acetate or other organic-derivative of cellulose are stretched in the presence of steam or hot water by means of an apparatus comprising a stretching chamber and an end pressure chamber or end pressure chambers containing a compressed inert fluid, and means are provided to maintain the temperature of the inert fluid in the end pressure chamber or chambers substantially below that of the steam or In carrying out the processes dc;

hot water. The invention also includes apparatus provided with such means.

Various methods and apparatus may be employed according to the present invention. Thus pipes or other devices through which cooling fluids are passed may be provided in the end chamber, or water or other suitable liquid may be forced into the chamber in order to reduce the temperature. Again, the compressed air or other compressed fluid supplied to the end pressure chamber may be cooled to a suitable temperature, for example 0 C. or even lower. An other method which may be employed comprises the use of an end pressure chamber of large dimensions so as to increase the cooling surface, while the material of which the chamber is made may be chosen for its good heat conductivity and may be blackened to increase its radiating power. The end chamber, whatever its dimensions, may be provided with fins, gills or the like to assist cooling. Further, the partition between the end and treatment chambers may be made of material of low heat conductivity. Again the chamber may be double walled so that a cooling liquid can be circulated around the inner wall or the chamber may be sprayed externally with a cooling liquid. Any suitable combination of the above methods may, of course, be employed. When two end chambers are employed both may be provided with the same or difierent means for reducing or preventing heating of the inert fluid.

The inert .fluid may be maintained at a temperature of 40, or C. or even more below that of the treatment fluid. Thus steam or hot water may be employed at a temperature of or C. or more in the stretching chamber and the fluid in the end chamber or chambers may be maintained at a temperature of 60-80 C. or less e. g. 40 C.

While the invention has been described above particularly in relation to the stretching of artificial filaments and the-like in the presence of steam or hot water it is clear that the utility of the invention is not confined tosuch processes, but extends also to otherprocesses in which travelling filaments, foils and similar materials are subjected to treatment with agents, e. g. shrinking or saponifying agents, at elevated temperatures in apparatus comprising one or more end chambers and a treatment chamber and heating up of the inert fluid in the end grammatically various forms of apparatus according to the present invention, wherein Figure 1 is a longitudinal cross-section of an apparatus suitable for stretching cellulose acetate yarns in the presence of steam,

Figure 2 is a longitudinal cross-section of a similar apparatus provided with two end chambers which have different means for reducing the temperature of the inert fluid contained therein,

Figures 3 and 4 are examples of other types of end chambers provided with cooling means which may be employedin place of the chambers illustrated in Figures 1 and 2.

Referring to Figure 1 the threads I from a creel of bobbins 2 pass through small orifices 3 into an end chamber 4 in non-slipping contact with nip rollers 5 in the end chamber, through small orifices 6 into a steam chamber I, out of the steam chamber through orifices 8 in non-slipping contact with nip rollers 9 for stretching and are finally'wound on a creel of bobbins Ill. Compressed air or other inert fluid is introduced through the inlet II into the chamber 4 which is provided with a pressure gauge I2, a pressure relief valve I3 and a steam trap I4. A system of tubes 25 is provided through which cold water or other cooling fluid is circulated. Steam enters through perforated pipes I5 so positioned that wet or saturated steam is directed on to the threads immediately on their entry into the steam chamber I. The chamber I is also provided with a pressure gauge I6, a pressure relief valve I! and a steam trap I8.

Referring to Figure 2 the threads I pass through small orifices 3 into an end chamber 4, containing compressed air or other compressed inert fluid, in non-slipping contact with nip rollers 5, through small orifices 6 into a steam chamber I, out of the steam chamber through orifices 8 into an end chamber I9 containing compressed air or other compressed inert fluid, in non-slipping contact with nip rollers 9 for stretching, and finally out of the chamber through orifices 20 to a take-up device. The compressed inert fluid is introduced into chambers 4 and is through the inlets II and 24. The chamber 4 is double walled, cold water being introduced through the inlet 28 into the space 21 so that it circulates round the chamber and emerges through the outlet 28. The end chamber I9 is provided with cooling means which consist of fins II projecting from the walls of the chamber. The end chambers are also provided with pressure gauges I2 and 2|, pressure relief valves I3 and I2, and steam traps I4 and 23. Steam enters the steam chamber through perforated pipes I5 I so positioned that wet or saturated steam is directed on to the materials immediately on their entry into the steam chamber. The chamber is also provided with a pressure gauge I6, a pressure relief valve I1 and a steam trap I8.

Figure 3 shows another form of end chamber in accordance with the present invention which is provided with jets 30 through which a cooling liquid may be introduced into the chamber, and a steam trap I4 to allow the liquid to escape.

Figure 4 shows another form of end chamber which comprises sprays 3| directed against the outside of the end chamber, the cooling liquid being collected by the catch tray 32.

The following is an example of the production of yarn or improved tenacity in accordance wit the process of the present invention.

Dry spun cellulose acetate yarn is passed from a creel oi bobbins or other suitable source of supply through an apparatus similar to that illustrated in Figure 1 which contains compressed air in the end chamber and wet steam at a pressure of about 30 pounds per square inch above atmospheric pressure in the steam chamber. During its passage through the steam chamber it is stretched between the nip rollers 5 and 9 to about 10 times its original length and then taken up on a suitable device. The pressure of the air in the end chamber is about 28 pounds per square inch, and by passing cooling liquid through the tubes 25 the temperature of the air in the chamber is maintained at about 40-50 C.

Yarn of improved tenacity may be obtained in a similar manner using instead of an end chamber illustrated in Figure 1 an end chamber similar to that illustrated in Figure 3, the temperature of the air in the end chamber being maintained at about IO-80 C. by .spraying cold water under pressure into the chamber through the sprays 30.

The operative conditions described in U. S. application S. No. 17,242, filed April 19, 1935, may be employed in the process of the present invention. Thus artificial filaments made of cellulose acetate may be stretched in wet steam at a temperature of 120 C., 130 C. or more to 5, 10, or even more times their original length, and in this manner products having a tenacity of 4-6 gms./denier or more may be obtained. As in the prior specification the air or other inert fluid is preferably at a pressure only slightly below that of the treatment fluid, e. g. a pressure of 1, 2 or 4 pounds per square inch lower.

It has further been discovered that the characteristics of the yarn obtained by steam or hot water stretching operations, such as are described in the above specification may be controlled by adjusting the dimensions and shape of the outlet orifices from the stretching chamber. Thus small orifices which tend to cause a turbulent flow and iso-thermal expansion of fluid issuing from them in general tend to increase the compactness of the yarn, and increase its resistance to aftertreatment agents, such as shrinking agents or dyestufis. Conversely increasing the dimensions of the orifices or shaping them so as to promote adiabatic expansion conditions in steam issuing from them, tends to decrease the compactness of the yarn and to render it more easily affected by after-treatment processes. The size of the orifices for stretching yarns may for example be of the order of .4 to .8 mm. depending upon the denier of the yarn employed as starting material and on the degree of stretch. The strength, extension, compactness and other properties of the stretched yarn obtained may be controlled by variation in the stretching conditions, such as the degree of stretch, the steam pressure and temperature and the position and dimensions of the steam jets. By varying the conditions, products having a tenacity of 3-6 gms./denier may be obtained.

Having described our invention what we desire to secure by Letters Patent is:

1. Process for the treatment of threads, foils and similar materials with fiuid media under pressure, which comprises running the materials from the outer air into an end chamber, which contains a compressed inert fluid and which communicates with a pressure treatment chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and treatment chambers into a hot treat- I ment fluid under pressure contained in the treatment chamber and finally into the outer air, and maintaining the temperature of the inert fluid substantially below that of the treatment fluid.

2. Process for improving the tenacity of threads, foils and similar materials made of organic derivatives of cellulose, which comprises running the materials from the outer airinto an end pressure chamber, which contains a compressed inert fluid and which communicates with a stretching chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains wet steam under pressure at a temperature above C., and finally into the outer air and stretching the materials whilst in the steam, the pressure of the inert fluid being at the most substantially the same as that of the steam and its temperature being maintained substantially below that of g the steam.

3. Process for improving the tenacity of threads, foils and. similar materials made of organic derivatives of cellulose, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert fluid and which communicates with a stretching chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains hot water under pressure at a temperature above 100 C., and finally into the outer air and stretching the materials whilst in the hot water, the pressure of the inert fluid being at the most substantially the same as that of the hot water and its temperature being maintained substantially below that of the water.

4. Process for improving the tenacity of filaments, threads and similar materials made of organic derivatives of cellulose, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert gas and which communicates with a stretching chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains wet steam under a pressure higherthan that of the inert gas and at a temperature above 100 C., and from the stretching chamber directly into the outer air, and stretching the materials whilst in the steam, the temperature of the inert gas being maintained substantially below that of the steam.

5. Apparatus for the treatment of travelling filaments, foils and similar materials with a fluid treatment agent under pressure, which comprises in combination a pressure treatment chamber and an and pressure chamberior inert fluid containing a positively driven feed device for the materials and provided with an inlet for inert fluid and with means adapted to maintain the temperature of the inert fluid substantially below that of the treatment agent, said chambers having' orifices to permit passage of the materials from the outer air through said chambers into the outer air again. r

6. Apparatus for stretching filaments, threads and similar materials in a fluid stretch assisting agent under pressure, which comprises in combination a pressure stretching chamber for stretch assisting agent having an inlet for stretch assisting agent, an end pressure chamber for inert fluid, containing a positively driven feed device for the materials and provided with an inlet for inert fluid and with means to maintain the temperature of the inert fluid substantially below that of the treatment agent, and a second positively driven feed device adapted to draw the materials through and stretch them in the stretching chamber, said chambers having orifices to permit passage of the materials from the outer air through said chambers into the outer air again.

7. Process for improving the tenacity of filaments, threads and similar materials made of cellulose acetate, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert gas and which communicates with a stretching chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains wet steam under a pressure higher than that of the inert gas and at a temperature above C. and from the stretching chamber directly into the outer air, and stretching the materials whilst in the steam, the temperature of the inert gas being maintained substantially below that of the steam.

8. Process for improving the tenacity of filaments, threads and similar materials made of cellulose acetate, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert fluid and which communicates with a stretching chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains hot water under a pressure higher than that of the inert fluid and at a temperature above 120 C. and from the stretching chamber directly into the outer air, and stretching the materials whilst in the hot water, the temperature of the inert fluid being maintained substantially below that of the hot water. 7

9. Process for improving the tenacity of threads, foils and similar. materials made of organic derivatives of cellulose, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert fluid and which communicates with a stretching chamber, in substantially nonslipping contact with a postively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains wet steam under pressure at a temperature above 100 C., and finally into the outer air and stretching the materials whilst in the steam, the pressure of the inert fluid being at the most substantially the same as that of the steam and its temperature being maintained at least 40 C. below that of the steam. 4

10. Process for improving the tenacity of threads, foils and similar materials made of organic derivatives of cellulose, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert fluid and which communicates with a stretching chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains hot water under pressure at a temperature above 100 C.. and finally into the outer air and stretching the materials whilst in the hot water, the pressure of the inert fluid being at the most substantially the same as that of the hot water and its temperature being maintained at least 40 C. below that of the water.

11. Process for improving the tenacity of threads, foils and similar materials made of cellulose acetate, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert fluid and which communicates with a stretching chamher, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains wet steam under pressure at a temperature above 100 C., and finally into the outer air and stretching the materials whilst in the steam, the pressure of the inert fluid being lower, but only slightly lower, than that of the steam and its temperature being maintained at least 40" C. below that of the steam.

12. Process for improving the tenacity of threads, foils and similar materials made of cellulose acetate, which comprises running the materials from the outer air into an end pressure chamber, which contains a compressed inert fluid and which communicates with a stretching chamber, in substantially non-slipping contact with a positively driven feed device in the end chamber, thence through the communication between the end and stretching chambers into the stretching chamber, which contains hot water under pressure at a temperature above 100 C., and finallg into the outer air and stretching the materials whilst in the hot water, the pressure or the inert fluid being lower, but only slightly lower, than that of the hot water and its temperature being maintained at least 40 C. below that of the water.

13. Apparatus for stretching filaments, threads and similar materials in a fluid stretch-assisting agent under pressure, which comprises in combination a pressure stretching chamber for stretch-assisting agent havingan inlet for stretchassisting agent, an end pressure chamber for inert fluid, containing a positively driven feed device for the materials and provided with an inlet for inert fluid and with means for passing cooling fluid therethrough so as to maintain the temperature of the inert fluid substantially below that of the treatment agent, and a second positively driven feed device adapted to draw the materials through and stretch them in the stretching chamber, said chambers having orifices to permit passage of the materials from the outer air through said chambers into the outer air again.

14. Apparatus for stretching filaments, threads and similar materials in a fluid stretch-assisting agent under pressure, which comprises in combination a pressure stretching chamber for stretch-assisting agent having an inlet for stretch-assisting agent, an end pressure chamber for inert fluid containing a positively driven feed device for the materials and provided with an inlet for inert fluid and with means for spraying cooling fluid therein so as to maintain the temperature of the inert fluid substantially below that of the treatment agent, and a second positively driven feed device adapted to draw the materials through and stretch them in the stretching chamber, said chambers having orifices to permit passage of the materials from the outer air through said chambers into the outer air again.

HENRY DREYFUS. ROBERT WIGHTON MONCRIEFF. WILLIAM MACIN'IOSH GLASS. 

